<template>
  <div class="com-container">
    <div class="title" :style="comStyle">
        <span class="tt">{{ '▎'  + showTitle}}</span>
        <span :style="comStyle" class="iconfont title-icon" @click="showChoice = !showChoice">&#xe6eb;</span>
        <div class="select-con" v-show="showChoice" :style="marginStyle">
          <div  class="select-item" @click="handleSelect(item.key)" 
                v-for="item in selectTypes" :key="item.key">
            {{item.text}}
          </div>        
        </div>
    </div>
    <div class="com-chart" ref="trend_ref"> 
    </div>
  </div>
</template>

<script>
import {mapState} from 'vuex'
import { getThemeValue } from '@/utils/theme_utils'

export default {
  data () {
    return {
      chartInstance: null,
      allData: null, // 从服务器获取的所有数据
      showChoice: false, // 是否显示可选项
      choiceType: 'map', // 显示的数据类型
      titleFontSize: 0, // 指明标题的字体大小
    }
  },
  created() {
    // 在组件创建完毕后, 注册回调函数
    this.$socket.registerCallBack("trendData", this.getData)
  },
  mounted() {
    this.initChart()
    // this.getData()
    // 发送数据给服务器,告诉服务器,我现在需要数据
    this.$socket.send({
      action: 'getData',
      socketType: 'trendData',
      charName: 'trend',
      value: ''
    })
    window.addEventListener("resize", this.screenAdapter)
    this.screenAdapter()
  },
  destroyed() {
    window.removeEventListener("resize", this.screenAdapter)
    // 再组件销毁的时候,进行回调函数的取消
    this.$socket.unRegisterCallBack("trendData")
  },
  computed: {
    // 控制下拉菜单条目
    selectTypes() {
      if(!this.allData) {
        return []
      } else {
        return this.allData.type.filter(item => {
          return item.key !== this.choiceType
        })
      }
    },
    // 控制标题的数据
    showTitle() {
      if(!this.allData) {
        return ""
      } else {
        return this.allData[this.choiceType].title
      }
    },
    // 设置标题的大小
    comStyle() {
      return {
        fontSize: this.titleFontSize + 'px',
        color: getThemeValue(this.theme).titleColor
      }
    },
    // 对齐下拉菜单的选项
    marginStyle() {
      return {
        marginLeft: this.titleFontSize / 2 + 'px'
      }
    },
    ...mapState(['theme'])
  },
  watch: {
    theme() {
      console.log("主题切换了");
      this.chartInstance.dispose() // 销毁当前的图表
      this.initChart() // 重新以最新的主题名称初始化图表对象
      this.screenAdapter() // 完成屏幕适配
      this.updateChart() // 更新图表的展示
    }
  },
  methods: {
    // 初始化方法
    initChart() {
      this.chartInstance = this.$echarts.init(this.$refs.trend_ref, this.theme)
      const initOption = {
        grid: {
          left: '3%',
          top: '35%',
          right: '4%',
          bottom: '1%',
          containLabel: true,  // 显示坐标轴
        },
        tooltip: {
          trigger: 'axis'
        },
        legend: { // 图例的位置
          left: 20,
          top: '15%',
          icon: 'circle'
        },
        xAxis: {
          type: 'category',
          boundaryGap: false,  // 设置从y轴开始
        },
        yAxis: {
          type: 'value'
        }
      }
      this.chartInstance.setOption(initOption)
    },
    // 获取服务器数据方法

    // ret就是服务器发送给客户端的图表数据
     getData(ret) {
      // await this.$http.get()
      // 对allData进行赋值
      // const {data:ret} = await this.$http.get('trend')
      this.allData = ret
      console.log(ret);
      this.updateChart()
    },
    // 更新图表
    updateChart() {
       // 半透明的颜色值
      const colorArr1 = [
        'rgba(11, 168, 44, 0.5)',
        'rgba(44, 110, 255, 0.5)',
        'rgba(22, 242, 217, 0.5)',
        'rgba(254, 33, 30, 0.5)',
        'rgba(250, 105, 0, 0.5)'
      ]
      // 全透明的颜色值
      const colorArr2 = [
        'rgba(11, 168, 44, 0)',
        'rgba(44, 110, 255, 0)',
        'rgba(22, 242, 217, 0)',
        'rgba(254, 33, 30, 0)',
        'rgba(250, 105, 0, 0)'
      ]

      // 处理数据
      // timeArr x轴的数据 类目轴的数据
      const timeArr = this.allData.common.month
      // valueArr y轴的数据 series下的数据
      const valueArr = this.allData[this.choiceType].data
      const seriesArr = valueArr.map((item,index) => {
        return {
          name: item.name,
          type: 'line',
          data: item.data,
          stack: this.choiceType,
          areaStyle: {
            // color: new this.$echarts.graphic.LinearGradient(x1,y1,x2,y2, [])
            color: new this.$echarts.graphic.LinearGradient(0,0,0,1, [
              {
                // 0%颜色值
                color: colorArr1[index],
                offset: 0
              }, 
              {
                // 100%颜色值
                color: colorArr2[index],
                offset: 1
              }
            ])
          },
        }
      })
      // 图例的数据
      const legendArr = valueArr.map(item => {
        return item.name
      })
      const dataOption = {
        xAxis: {
          data: timeArr
        },
        legend: {
          data: legendArr
        },
        series: seriesArr
      }
      this.chartInstance.setOption(dataOption)
    },
    // 分辨率
    screenAdapter() {
      this.titleFontSize = this.$refs.trend_ref.offsetWidth / 100 * 3.6
      const adapterOption = {
        legend: {
          itemWidth: this.titleFontSize,
          itemHeight: this.titleFontSize,
          itemGap: this.titleFontSize,
          textStyle: {
            fontSize: this.titleFontSize / 2
          }
        }
      }
      this.chartInstance.setOption(adapterOption)
      this.chartInstance.resize()
    },
    handleSelect(currentType) {
      // 对点击想想进行处理
      this.choiceType = currentType
      this.updateChart()
      this.showChoice = false
    } 
  },
}
</script>
 
<style lang = "less" scoped>
  .title {
    position: absolute;
    left: 20px;
    top: 20px;
    z-index: 10;
    color: #fff;
    .title-icon {
      margin-left: 10px;
      cursor: pointer;
    }
    .select-con {
      background-color: #222733;
    }
  }
  .tt {
    font-weight: bold;
  }
</style>